Method for treating a yarn with foam

ABSTRACT

A FOAM IS CONTINUOUSLY MADE IN A HOLLOW BODY BY PRESSING A GASEOUS MEDIUM INTO A LIQUID. THE FOAM IS MADE FINER BY PASSAGE THROUGH AT LEAST ONE POROUS MEMBER, AND THEN CONTINUOUSLY APPLIED TO A YARN MOVING ACROSS AN OUTLET FOR THE FOAM AND THROUGH A FOAM AGGLOMERATION FORMING AT THE OUTLET. THE FOAM-FORMING LIQUID IS A YARNFINISHING AGENT, SUCH AS A SMOOTHING POLISH, A STIFFENING AGENT, OR A DYE.

Oct. 10, 1972 v. STRITZKO METHOD FOR TREATING A YARN WITH FOAM 2 Sheets-Sheet 1 Filed July 29, 1970 g ml a ub m I L mm V F. r m /..0 NM 0 mil fi Y B Get. 10, 1972 v. STRITZKO 3,697,314

METHOD FOR TREATING A YARN WITH FOAM Filed July 29, 1970 2 Sheets-Shed z AMI! fh-/ Iii/7 United States Patent 3,697,314 METHOD FOR TREATING A YARN WITH FOAM Vilem Stritzko, Zofingen, Switzerland, assignor to Bleiche AG, Zofingen, Switzerland Filed July 29, 1970, Ser. No. 59,131 Claims priority, application Switzerland, July 30, 1969, 11,579/ 69 Int. Cl. B44d N02 US. Cl. 117-120 6 Claims ABSTRACT OF THE DISCLOSURE A foam is continuously made in a hollow body by pressing a gaseous medium into a liquid. The foam is made finer by passage through at least one porous member, and then continuously applied to a yarn moving across an outlet for the foam and through a foam agglomeration forming at the outlet. The foam-forming liquid is a yarnfinishing agent, such as a smoothing polish, a stiffening agent, or a dye.

BACKGROUND OF THE INVENTION The present invention relates to a method for polishing and/or surface-dyeing, or stiffening aeyarn, and to apparatus for transforming a finishing agent for textile yarns into a foam which is applied to a yarn.

In accordance with the prior art, yarns are polished and stiffened by applying a liquid finishing agent by a rotating roll to the yarn, the roll being partly immersed into the liquid along its lower segment, and in contact with the yarn on the upper segment so that the yarn is moistened. The apparatus has the disadvantage that it cannot be built into existing machines, and another disadvantage is that the exact measuring out of the amount of liquid applied to the yarn is practically impossible. It is also known to apply the finishing liquid to a wound yarn coil. Since the yarn comes in contact with the liquid agent only on one side, the distribution of the finishing agent is unsatisfactory.

It is also known to inject the finishing agent into a finished wound coil. This method also results in an uneven distribution of the liquid in the coil, and in an irregular treatment of the yarn. It is also known to press hard paraffin against the yarn during winding up of the same. This has the disadvantage that the yarn is subjected to stress, and another disadvantage resides in the uneven application of the paraffin, and in resulting undesired washing properties of a treated wool yarn.

SUMMARY OF THE INVENTION It is one object of the invention to overcome the disadvantages of known methods for treating yarn with a finishing agent, and to provide an arrangement which assures uniform application of measurable amounts of a finishing liquid to a yarn.,

Another object of the invention is to transform a finishing liquid into a foam before applying same to a yarn.

Another object of the invention is to produce a fine foam of a finishing liquid, and to continuously distribute the foam over a moving yarn.

Another object of the invention is to provide a method by which foam is used to polish, stiffen, or surfacedye a yarn.

In accordance with the invention, a primary foam is formed in a hollow body and transformed into a finer secondary foam by passing through the porous means. The fine'foam is then discharged through a discharge opening for covering a yarn sliding on the slide surface of distributing means. The pressure gas is preferably air compressed by a compressor and regulated by a valve.

The invention has the advantage that an amount of liquid of only 25-100 g., can be applied in the form of foam to a yarn of the length of 54,000 m. within one hour.

In accordance with the invention, a coarse foam is first formed of the finishing liquid, and then transformed into a fine foam which is applied to the yarn. This has the advantage that the primary foam, which has a lower friction resistance, can be transported in conduits without losses so that the foam producing part of the apparatus can be disposed spaced from the region in which the foam is applied through the distribtuing means to the yarn. The fine foam, however, which is applied to the yarn, permits a better distribution of the finishing liquid than would be possible with coarse foam.

The novel features which are considered as characteristic for the invention are set forthin particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a schematic elevation, partially in section, illustrating a first embodiment of the invention;

FIG. la is a sectional view taken on line IAIA in FIG. 1;

FIG. 2 is a schematic elevation, partially in section, and illustrating a second embodiment of the invention;

FIG. 2a is a sectional view taken on line IIAIIA in FFIG. 2; and

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIGS. 1 and 1a, a container 1 has a venting valve 2, and a filling opening which is closed by a cover 21 through which a foam-forming liquid F is filled into container 1 to the level 24. A hollow tubular body 3 is located in container 1 surrounded by the liquid F, and has a first inlet 4 at its lower end, and an outlet 16 on its upper end which is located above container 1 and the liquid level 24. Pressure gas supply means include a compressor, not shown, pressing air through a control valve 6 and conduit 5 into the inlet 4 of the hollow tubular body 3 so that the ball of a ball valve 13 is displaced from its seat surrounding inlet 4. A manometer 7 indicates the pressure in conduit 5.

A pressure conduit 8 supplies air through a pressurereducing valve 9 and a pressure gauge 10* to the upper portion of container 1. The interior of the tubular body 3 communicates through a conduit 11 with the interior of container 1, and the amount of liquid F flowing from container 1 through conduit 11 and a second inlet 14 into the tubular body 3 is determined by setting a regulating valve 12. Between the ball valve 13 and inlet 14, a .partitioning wall 15 extends across the entire cross-section of tubular container 3. The partitioning wall 15 consists of a porous material, and participates in the formation of foam by the gravity-operated ball valve 13.

The outlet 16 of the tubular body 3 is continued as distributing conduit means including a tubular portion 17, and a plurality of branch conduits 19, which may have any desired length, and each of which terminates in a tubular end portion closed by a wall 20, and having a longitudinally extending narrow dischargeslot 22. The lower part of the tubular distributor portion constitutes a slide face for a yarn, not shown. Each distributing branch conduit 19 may terminate at a different location for treating yarn spaced a considerable distance from the foamforming apparatus.

Between the inlet 14 for the liquid and the outlet 16 for foam, another partitioning wall 23, consisting of a porous material, extends across the entire cross-section of the tubular body 3.

The embodiment of FIG. 1 is operated as follows:

The foam-forming liquid, such as a polishing agent or stiffening agent for finishing a textile yarn, is filled into container 1 to, the level 24, whereupon the closure 21 of the filling opening is fluid-tightly closed. The level 24 of the liquid F is selected to be below the inlet in container 1 through which pressure air is supplied from conduit 8. When the regulating valve 12 is opened, the liquid F flows through conduit 11 and inlet 14 into the hollow tubular container 3 above the porous partitioning wall 15.

Upon opening of the pressure-reducing throttling valve 6, air under pressure passes through inlet 4 and ball valve 13, displacing the ball against the action of gravity, and then passes through the porous partitioning wall 15 so that the foam-forming means 13, 15 transforms the liquid entering the inlet 14 into tubular body 3 into a foam which is pressed upwards against the porous wall 23 at a pressure P Regulating valve 12 is correspondingly adjusted so that a pressure P of the air L above level 24, is greater than the pressure P in the tubular body 3. By adjusting .valves 6, 9 and 12, the fineness of the foam can be varied and adjusted.

The primary foam developed in the tubular body 3 is pressed through partitioning wall 23so that the primary rather-coarse foam is transformed into a finer foam which is transported by the pressure P into the distributing tube 17 and .the branch conduit 19 to, and out of the discharge slot 22 for being applied to a moving yarn which slidingly engages the distributing tube in the region of discharge slot 22.

It has been found that the coarse primary foam has a lesser flow resistance than the fine secondary foam, and is consequently more suitable for flowing through conduits, whereas the fine secondary foam assures a better distribution of the finishing agent over the length of the yarn. Consequently, if the location of the foam-forming apparatus is comparatively far from the locations at which the fine foam isapplied to the yarn, the second embodiment of FIG. 2 is preferred. The embodiment of FIG. 2 corresponds substantially to the embodiment of FIG. 1, and consequently corresponding parts are indicated by like reference numerals. A tubular body 3 is provided in a container 1 and has an inlet 4 for pressure air, and a second inlet 14 connected by a conduit 11 with the interior of container1,.a regulating valve 12 being provided in conduit 11. As compared with FIG. 1, the means for supplying pressure air to container 1 are omitted, and the liquid Fflows through regulating valve 12, conduit 11,

4 and inlet 14 into the tubular body 3 due to the hydrostatic pressure caused by the height H of the liquid level 24 above the inlet 14. The pressure P in tubular body 3 is equal to the pressure P in the air space L.

The porous partitioning wall 23 of the embodiment of FIG. 1 is omitted, and replaced by a part-cylindrical porous plate 23', located in, and fluid-tightly fitting into a tubular distributing portion having a discharge slot 22. Due to this arrangement, the coarse primary foam flows in the distributor conduit or conduits 19 with little flow resistance, and is transformed by the porous means 23 into a fine secondary foam directly before the same is applied to a yarn sliding across the discharge slot 22.

FIG. 3 shows a modification of FIG. 2 in which two closed tubular distributor end portions 19' are disposed on opposite sides of a plane in which a yarn 26 is transported. Yarn 26 slides successively on the upper .and lower surfaces of the tubular distributor end portions, and across the respective discharge slots 22, so that the fine foam is applied to opposite sides of yarn 26 for uniformly covering the yarn.

In the embodiment of FIG. 2, an outlet 25 is provided in tubular body 3 above the level 24 of the liquid P so that the pressure P in the tubular body 3 is equal to the pressure P in the air space L.

In a simplified embodiment, not shown, the porous partitioning wall 15 is omitted, and the primary coarse foam is formed at the ball valve 4, 13. The second porous means 23 or 23' can be provided in the form of a wall 23, as in the embodiment of FIG. 1, or as a part-cylindrical plate 23, as in the embodiment of FIG. 2.

It is evident that a dye can be added to foam-forming liquids which are suitable for polishing and stiffening a yarn so that the yarn is also surface-dyed. It is also possible, to use a foam-forming liquid dye without addition I of a polishing or stiffening agent.

In accordance with the .method of the invention, a

liquid finishing agent is transformed into a foam, and the foam is applied to the surface of a moving yarn to obtain a uniform and very economical distribution of the finishing agent on the yarn surface. Preferably, the liquid is first transformed into coarse foam which is moved with low friction losses through conduit means, whereupon the coarse foam is transformed into a fine foam before being uniformly and economically applied to the moving yarn.

In the preferred method of the invention, the fine foam is supplied in a regulated amount to a warp yarn and to a weft yarn, and then uniformly distributed over the width of the warp.

The porous wall 15 may consist of a metal insert having bores with a diameter up to 0.5 mm.

The porous walls 23 and 23', respectively, may be metal inserts with finer bores than wall 15 or may consist of an inserted piece of a fabric or felt. 7

As a polishing agent, a liquid wax or paraflin mixed with a commonly used synthetic wetting agent may 'be used.

As a stiffening agent a starch solution containing a.

or aggregation assures a uniform distribution of theagent over the surface of the yarn.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of arrangements for applying a finishing agent to a yarn differing frornthe types described above.

While the invention has been illustrated and described as embodied in a method for continuously treating the surface of a yarn with a foam formed of a liquid finishing agent, it is not intended to :be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that from the standpoint of prior art fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

What is claimed is:

'1. Method for applying a coating to a moving yarn, comprising continuously generating foam and supplying an amount of the generated foam to an outlet so that a foam aggregation forms outside of said outlet; moving at least one yarn in longitudinal direction thereof across said outlet and through said foam aggregation whereby aggregated foam is applied to successive portions of said yarn to form a coating thereon so that a part of the aggregated foam is conveyed away from said foam aggregation by said moving yarn; and regulating the amount of foam supplied to said outlet so that foam conveyed away by said yarn is continuously replaced, and a substantially constant foam aggregation is maintained for the passage of said yarn therethrough so that the thickness of said coating remains substantially contant.

2. The method of claim 1 wherein said foam is generated in a hollow body located at a distance from said outlet, and supplied to said outlet through a conduit at a regulatable pressure differential.

3. The method of claim 2 wherein a coarse foam is generated for flowing through said conduit at low flow resistance; and comprising transforming the coarse foam into a fine foam before said foam is discharged through said outlet.

4. The method of claim 3 wherein said step of transforming said foam comprises passing said coarse foam through a porous body covering the inside of said outlet.

5. The method of claim 1 wherein said outlet is an elongated slot in a surface; and wherein said moving yarn slides on said surface across said slot in a direction per- .pendicularly to said lot.

6. The method of claim 1 comprising generating said foam of a liquid containing a finishing agent for said yarn so that said coating contains said finishing agent.

References Cited UNITED STATES PATENTS 1,102,088 6/ 1914 Schmid 8-19 1,948,568 2/1934 Faber et al. 819 3,235,400 2/1966 Voelker 117120 XR EDWARD G. WHITBY, Primary Examiner US. Cl. X.R. 

